Using System Software Chapter 5

Announcements  Chapter 5 Homework  Windows 7 Homework

Objectives  System Software  Categories of Operating Systems (OS)  OS’s role in:  Providing user interaction  Managing the processor  Managing memory  Managing hardware  Interacting with application software  Starting the computer  Desktop & window features  OS’s role in keeping the desktop organized  Utility Programs

System Software: The OS  Controls all computer functions:  Hardware, Processor, Memory, Peripherals  Manages how applications run on the CPU  Provides user interface such as desktop, icons, an menus

System Software: Utilities  Utilities: Software that performs “housekeeping” tasks  Backup  Security  Diagnostics  Recovery  Optimization

Operating System Categories  Four primary categories of operating systems:  Single-User, Single Task  MS-DOS  Single-User, Multi-Task  Microsoft Windows, Apple iOS, Linux  Multi-User (Network Operating System)  Microsoft Windows Server, Linux, Unix  Real-time (RTOS): Embedded System  Found in cars, instruments, tools

Real-Time Operating Systems  Systems with a specific purpose and a certain result  Uses include:  Automobiles  Printers  VoIP phones  Medical devices  Appliances  Robotic equipment

Multi-User Operating Systems  Known as “Network Operating Systems”  Allow access to the computer system by more than one user  Manage user requests  Systems Include:  Linux  UNIX  Windows Server  IBM z/OS

UNIX  Multi-User, Multi-Task operating system  Used primarily with mainframes  Also found in PCs  Vendors can modify the code  Hewlett-Packard HP/UX  Sun Solaris  IBM AIX

Mainfames & Supercomputers  Other computers utilizing multi-user operating systems  Mainframes  Handle requests from hundreds and thousands of users simultaneously  Supercomputers  Used by scientists and engineers

Smartphones  Do more than let the user make and answer phone calls  Have productivity features like web browsing, , multimedia, cameras, etc.  Example: Android, iPhone, Windows Phone, Blackberry

Desktop Operating Systems  An operating system combined with a processor is known as a platform  Microsoft Windows & Intel/AMD  Apple Mac OS & Motorola/Intel  Application software is OS specific, not platform specific

Microsoft Windows  Multi-user, multi-tasking OS  Windows 8 is the newest version  Features  Increased functionality  User-friendliness  Improved Internet capabilities  Enhanced privacy and security

Mac OS  First commercially available OS with point & click technology (GUI)  Graphical User Interface  Excellent in:  Graphics  Processing  System reliability  File backup  Based on Linux OS  Fewer applications available vs. Windows  Much more expensive (2x-4x)

Linux  Open source operating system  Based on UNIX  Extremely stable  May be downloaded for free!  Can be modified by anyone to meet any need  Runs on PCs, phones, MP3 players, multimedia systems, servers, cars, etc..

What the OS does  Provides a user interface  Manages the CPU  Manages memory and storage  Manages hardware and peripheral devices  Coordinates application software with the CPU

The User Interface  Enables you to interact with the computer  Types of interfaces:  Command-line Interface  Menu-driven Interface  Graphical User Interface (GUI)

Command Line Interface

Menu Driven Interface

Graphical User Interface (GUI)

Processor Management  Controls the timing of events the processor works on  Multitasking  Interrupts  Interrupt Handler  Interrupt Table  Stack

Multitasking  The OS controls the execution of instructions on the CPU  Decides when each application is allowed to run and for how long  Assigns each process a slice of time (time slice) and switches between each process rapidly (measured in milliseconds).  The ability to do multiple things at once (or appear to do so) is called Multitasking.

Interrupts  Some functions of the computer must be handled immediately  Mouse  Keyboard  Audio  Printer  When an “Interrupt Request” is made by these devices, the CPU stops executing programs and takes care of the needs of the device

Stack  Last In, First Out (LIFO)  Common sense analogy: A stack of paper  OSs and CPUs use stacks to remember how to get back to where it was after processing an interrupt  Stack Operations:  Peek: Take a look at what is on top of the stack without removing it  Pop: Remove and process the top item  Push: Place a new item on the stack

OS Architecture  32-bit Architecture  Each instruction is up to 32 bits long  Each location in memory is exactly 32 bits long  Can use up to 4GB of RAM  64-bit Architecture  Each instruction is up to 64 bits long  Each location in memory is exactly 64 bits long  Can use up to 512GB of RAM  Correction to book:  Systems with more than 4GB of RAM feature a 64-bit version of Windows  Systems with more than 4GB of RAM must use a 64-bit operating system to make use of extra memory.

Random Access Memory (RAM)  RAM has limited capacity  Running multiple programs at one time requires more RAM  Operating System consumes RAM  Windows Vista: 1.5GB  Windows 7: 1GB  Windows 8: 512MB (possible to use less)

Virtual Memory  Instructions and data are stored on the hard drive when RAM is full  Swap file  Paging  Thrashing

Hardware and Peripheral Device Management  Device drivers  Programs that enable the operating system to communicate with peripheral devices  Provided by the manufacturer of the device  Plug & Play  Hardware and software standard  Facilitates the installation of new hardware

Software Application Coordination  Application programming interfaces (APIs)  Blocks of code contained in the OS  Coordinate the OS with software applications  Similar toolbars and menus  Example:  Microsoft DirectX  OpenGL

 The boot process  Basic Input Output System (BIOS) is activated  A Pre-Operating System Test (POST) checks attached hardware  The OS loads into RAM  Configuration and customization settings are checked BIOSPOSTOS Starting the Computer

Handling Errors in the Boot Process  Safe Mode  Windows does not boot properly  Try rebooting  Uninstall any new devices or software  Press F8 after the POST and before the Windows Logo appears.  Can be tricky, sometimes helps to press repeatedly until safe mode menu appears.

The Windows 7 Desktop Start Button All Programs Recycle Bin System Tray Control Panel Documents Desktop Task Bar Start Menu

The Windows 8 Start Screen Icons Switch to Desktop

The Windows 8 Desktop System Tray Desktop Task Bar Recycle Bin

The Mac iOS Start Screen Icons Task Bar

The Mac iOS Desktop Trash Settings System Tray Apple Menu Application Menu Desktop Task Bar

The Linux (Ubuntu) Desktop Desktop System Tray Application Menu Task Bar Trash

Windows Title Bar Control Box (Min, Max, Close) Ribbon Zoom Document View

 Side by Side  Stacked  Cascading  Flip 3D  Snap Viewing Windows

File Management  The operating system provides an organizational structure for the computer’s contents  Hierarchical structure of directories:  Drives  Folders  Subfolders  Files  Windows Libraries

File Management Quick Links Libraries Files & Folders

Viewing and Sorting Files and Folders  Many views available  Large Icon view  Extra Large Icon view  Tiles view  Details view  List view  Small & Medium Icon views

File Name Extensions ExtensionType of DocumentApplication.docWord processingMicrosoft Word 2003.docxWord processingMicrosoft Word xlsxSpreadsheetMicrosoft Excel pptxPresentationMicrosoft PowerPoint pdfPortable DocumentAdobe Acrobat.txtTextNotepad/Wordpad.jpgImagePaint.gifImagePaint.bmpImagePaint.zipCompressed File(s)File Explorer

Naming Files  The file extension determines which application will open the file by default  File name includes the name of the file plus an extension  Up to 255 characters  Names/Extensions ma not include the following characters:  “ / \ * ? | :  Mac* and Windows file names are not case sensitive  Linux file names are case sensitive and do not use extensions *It is possible to enable Mac file name case sensitivity.

The File Path  Describes the location of the file

Working with Files  File management actions  Open  Copy  Move  Rename  Delete  Recycle Bin / Trash

Utility Programs  Small programs that perform special functions  Manage System Resources (Task Manager)  Create a pleasant environment (Explorer)  Improve Efficiency (Defragment)

Display Utilities  Change the appearance of:  Desktop  Background  Screen Savers  Window Colors

Add or Remove Programs  Installation Wizard  Uninstall Wizard  Programs should uninstalled, deleting can cause errors

File Compression Utilities  Reduce the size of a file  Make it easier and faster to send files over the Internet  Work by replacing repeating segments with a short placeholder.

 Disk Cleanup: Removes unnecessary files  Choose the files to be deleted  Downloaded program files  Temporary Internet Files  Offline Web Pages  Recycle Bin  Disk Defragmenter: Speeds up access to files  Error Checker: Check for lost/damaged files  Task Manager: Check on nonresponsive programs System Maintenance Utilities

System Restore  Restores system settings to a specific date  Restore utility will describe what was installed and when (Windows 8)

System Backup  Backup  Creates a copy of the hard drive to another storage device  Task Scheduler  Runs selected utilities automatically

 Ease of Access Center  Centralized location for assistive technology  High Contrast  Magnifier  On-screen keyboard  Windows speech recognition Accessibility Utilities